An incompetent person, especially in new companies. Bozos have a net negative effect on morale and profits, and everyone knows it.
I first heard this specific meaning of "bozo" during a talk to business students by one of Yahoo's founders.

Q: "What's the most important thing to do in order to grow your company from 10 employees to 100 or 1000?"
A: "Get rid of the bozos. Seriously, fire them immediately."